import { Transform } from 'node:stream'

// This is a buffering parser, have a look at StreamingQuerystring.js for a streaming parser
class QuerystringParser extends Transform {
  constructor(options = {}) {
    super({ readableObjectMode: true })
    this.globalOptions = { ...options }
    this.buffer = ''
    this.bufferLength = 0
  }

  _transform(buffer, encoding, callback) {
    this.buffer += buffer.toString('ascii')
    this.bufferLength = this.buffer.length
    callback()
  }

  _flush(callback) {
    const fields = new URLSearchParams(this.buffer)
    for(const [key, value] of fields) {
      this.push({
        key,
        value,
      })
    }
    this.buffer = ''
    callback()
  }
}

export default QuerystringParser
